It is a common practice for law enforcement and security personnel to carry one or more restraining devices, such as handcuffs, on their person when carrying out an operation where restraining devices may be deployed. Such restraint devices are generally used when needed to secure a subject's wrists for restricted hand and arm movement. Typical wrist restraint devices take the form of metallic handcuffs that include lock mechanisms operative to prevent unintended release of the handcuffs once applied to a subject's wrists. The keys for releasing handcuff lock mechanisms are generally relatively small, have an unlocking paddle mounted on or formed integral with a shank in a generally “L” shaped profile, and are typically adapted to be retained on a key ring. However, due to the size and configuration of other keys carried on the key ring, and the key ring configuration itself, a handcuff key can sometimes be difficult to quickly locate by security and law enforcement personnel who carry a key ring having a plurality of keys thereon besides the handcuff key. Other problems sometimes experienced by personnel whose duties require that they carry such handcuff keys include snagging of the generally “L” shaped key on the user's clothing, such as pants or a jacket pocket in which the key ring is carried, often ripping the pocket or adjacent clothing.
Another problem sometimes experienced with such handcuff keys is the potential for injury due to the key jabbing the leg of a person who carries the key in his pocket or on a key ring carried on the person's belt so that the keys dangle. Because the key is generally “L” shaped, the locking paddle or tooth of the key, which is generally perpendicular to an elongated key handle or shank, is typically disposed perpendicular to the officer's leg and can be inadvertently forced against the leg in a jabbing action so a to cause pain and injury, in addition to damaging the clothing. Further, as noted, handcuff keys are relatively small and are typically held on the same key ring as other keys (including, for example, car keys, office keys and the like), so that it can be difficult to quickly locate the handcuff key on the key ring. Moreover, even after the handcuff key is located, it is often difficult to manipulate the key to a position to open a restraint device when carried on a heavy or over-laden key ring. This can lead to endangerment of the officer if his or her attention is directed away from an apprehended suspect. Also, because keys are often kept in one's pocket, in some situations it can be inconvenient for another officer to have access to the handcuff key when the officer having possession of the key is incapacitated or unable to assist in the retrieval of the keys.
It has generally been considered impractical to change the shape of known handcuff keys because of the large number of handcuffs presently in existence that use only this key design. Typically, all police keys and handcuffs are interchangeable, and changing the basic key configuration can have significant economic and operational impact. Furthermore, keys of a different shape may still exhibit at least some of the aforementioned problems in respect to quick retrieval and use when carried on a key ring.
Attempts have been made to solve the aforedescribed problems associated with known handcuff keys. See, for example, U.S. Pat. No. 5,568,741 (“the '741 patent”) that is assigned to the assignee of the present invention and incorporated herein by reference. This patent discloses different embodiments of a handcuff key in combination with other commonly used devices. For example, the key can be concealed inside a pen enclosure, such as beneath the pen cap, or in a folding pocketknife as a separate “blade,” or in other novelty casings, such as a nail clipper or pocket-folding tool. One of the purposes of the devices disclosed in the '741 patent is to provide concealed placement of a handcuff key. Such concealment is often important in undercover assignments and crowd control where concealment is necessary to the officer's safety, but is generally unnecessary in day-to-day assignments where convenience and ease of use of a handcuff key are paramount considerations. Under any condition, a handcuff key should be readily accessible and usable without undue loss of time during retrieval and preparation for use.